User's Manual

xE70-915 RF Module User Guide
1VV0301106 rev.3 – 2015-03-04
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4.5. Signals Description
Signals Description
Reset
External hardware reset of the radio module.
Active on low state.
TXD, RXD
Serial link signals, format NRZ/TTL:
TXD is for outgoing data. RXD is for incoming data.
The ‘1’ is represented by a high state.
CTS
Incoming signal. Indicates whether the module can send serial data to
user (Active, on low state) or not (inactive, on high state).
RTS
Outgoing signal. Indicates whether the user can transmit serial data
(active, on low state) or not (inactive, on high state).
IO
I/O, configurable as input or as output.
See reference document [2] for LE70-915.
STANDBY
Input signal which indicates to the module to switch to pre-selected low-
power mode. See reference document [2] for LE70-915
TX LED
Output signal set to VCC during radio transmission and set to GND the
rest of the time
RX LED
Output signal set to VCC as soon as a radio frame is detected with correct
synchronization word. The signal returns to GND as soon as the frame
reception is finished
ACK TX
In Addressed Secured mode, this signal rises to VCC when an ACK
hasn’t been received after frame transmission and repetition. This is the
hardware version of “ERROR” serial message. It stays at VCC until next
success addressed secured transmission
STATUS TX/RX
Output signal which indicates the status of the serial port. When serial
port is transmitting, Status RX/TX signal goes VCC until the end of serial
transmission. The signal stays to GND the rest of the time